Introduction: Persistent Müllerian duct syndrome (PMDS), or uterus masculinus, is a rare autosomal recessive form of male pseudohermaphroditism due to the failure of paracrine anti-Müllerian hormone (AMH) secretion by Sertoli cells or failure of the Müllerian ducts to respond to AMH secretion. The malignant degeneration of persistent Müllerian remnants is rare. In human medicine, few related reports exist. In veterinary medicine, this is the first report describing adenocarcinoma of the uterus masculinus involving the prostate in a dog.

Clinical history: An 11-year-old, male, neutered Pomeranian dog was referred for computed tomography due to the suspicion of prostatic carcinoma based on ultrasound and cytological examinations. The computed tomography findings were consistent with a uterus masculinus mass with possible prostatic infiltration. Uterus masculinus removal and total prostatectomy were performed; termino-terminal urethral anastomosis was carried out. Dehiscence of the anastomosis was observed 3 days after surgery. The owner declined any further procedures, and the dog was euthanized 5 days after surgery. Histopathological evaluation revealed adenocarcinoma of the uterus masculinus.

Conclusion: Adenocarcinoma of the uterus masculinus may occur, suggesting that patients with PMDS should be evaluated for malignant changes of Müllerian remnants.

介绍：持续性苗勒管综合症（PMDS）或子宫阳具，是一种罕见的常染色体隐性形式的男性假性雌雄同体性激素，这是由于Sertoli细胞分泌的旁分泌抗苗勒管激素（AMH）失败或苗勒管无法响应AMH分泌。持续发生的苗勒氏残余物恶变很少。在人类医学中，很少有相关报道。在兽医学中，这是描述狗累及前列腺的子宫男性子宫腺癌的首次报道。

临床病史：由于怀疑根据超声和细胞学检查发现前列腺癌，因此将一只11岁的雄性绝育的博美犬狗转入计算机体层摄影术。电脑断层扫描的发现与可能有前列腺浸润的子宫阳cul肿块相符。进行子宫阳cul切除术和全前列腺切除术；进行了末端尿道吻合术。术后3天观察到吻合口裂。主人拒绝任何进一步的手术，并且在手术后5天对这只狗实施了安乐死。组织病理学评估显示子宫肌瘤腺癌。

结论： 可能会发生子宫肌层腺癌，这提示应对患有PMDS的患者进行穆勒氏残余物恶性变化的评估。